Bed siderail apparatus

ABSTRACT

A patient support is provided having a frame, a mattress, and at least one siderail. The siderail includes a rail member and a coupler configured to permit raising and lower of the rail member between a lowered egress position and a raised blocking position.

[0001] This application is a divisional of U.S. application Ser. No.10/079,126, filed Feb. 19, 2002, which is a continuation-in-part of U.S.application Ser. No. 09/750,741, filed Dec. 29, 2000, now U.S. Pat. No.6,658,680, the disclosures of which are expressly incorporated byreference herein.

BACKGROUND AND SUMMARY OF THE INVENTION

[0002] The present invention relates to patient supports, such ashospital beds. More particularly, the present invention relates tosiderails for patient supports.

[0003] Hospital bed and other patient supports are known. Typically,such patient supports are used to provide a support surface for patientsor other individuals for treatment, recuperation, or rest. Many suchpatient supports include a frame, a mattress supported on the frame, andsiderails configured to block egress of a patient from the mattress.

[0004] According to one aspect of the present invention, a patientsupport is provided that includes a frame, a mattress supported by theframe, and a siderail supported by the frame. The siderail has a railmember and a linkage assembly. The linkage assembly is configured topermit movement of the rail member between a raised position blockingegress of a patient positioned on the mattress and a lowered position.The linkage assembly includes a first stationary cam member and a firstrotary cam member positioned to contact the first stationary cam memberto move the rail member along a longitudinal axis in a first directionwhen the rail member is moved to the lowered position. The linkageassembly also includes a second stationary cam member and a secondrotary cam member positioned to contact the second stationary cam memberto move the rail member along the longitudinal axis in a seconddirection opposite the first direction when the rail member is moved tothe raised position.

[0005] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress supported by theframe, and a siderail supported by the frame. The siderail has a railmember and a coupler. The coupler is configured to permit movement ofthe rail member between a raised position blocking egress of a patientpositioned on the mattress and a lowered position. The coupler includesa cam assembly configured to move the rail member in a first directionduring movement of the rail member.

[0006] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress positioned overthe frame, and a siderail. The siderail includes a rail member having alongitudinal axis and a linkage assembly configured to permit movementof the rail member between a raised position blocking egress of apatient positioned on the mattress and a lowered position permittingegress. The linkage assembly has a longitudinal axis that deviates frombeing perpendicular to and parallel with the longitudinal axis of therail member at all times during movement of the rail member from theraised to lowered position.

[0007] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress supported by theframe, and a siderail. The siderail includes a rail member and a couplerconfigured to couple the rail member to the frame. The rail member has alongitudinal axis. The coupler is configured to rotate the rail memberabout an axis of rotation. The axis of rotation deviates from beingperpendicular to and parallel with the longitudinal axis of the railmember at all times during movement of the rail member from the raisedto lowered position.

[0008] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress supported by theframe, and a siderail. The siderail includes a rail member having alongitudinal axis and a coupler configured to couple the rail member tothe frame and permit movement of the rail member between a raisedposition blocking egress of a patient positioned on the mattress and alowered position permitting egress. The coupler is configured to movethe rail member in a first longitudinal direction during all downwardmovement of the rail member from the raised position to the loweredposition.

[0009] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress positioned overthe frame, and a siderail. The siderail includes a rail member having alongitudinal axis and a coupler configured to permit movement of therail member between a raised position blocking egress of a patientpositioned on the mattress and a lowered position permitting egress. Thecoupler is configured to move the rail member in a first longitudinaldirection during lowering of the rail member to the lowered positionwithout moving in a second longitudinal direction opposite the firstlongitudinal direction.

[0010] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress positioned overthe frame, and a siderail. The siderail includes a rail member having alongitudinal axis and a coupler configured to couple the rail member tothe frame and to permit movement of the rail member between a raisedposition blocking egress of a patient positioned on the mattress and alowered position. The coupler is configured to move the rail member in alongitudinal direction and a sideways direction away from the mattressduring movement of the rail member between the raised and loweredpositions.

[0011] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress supported by theframe, and a siderail. The siderail includes a rail member and a couplerconfigured to permit rotation of the rail member about an axis ofrotation between a raised position and a lowered position. The axis ofrotation deviates from being horizontal when the mattress is in a flatbed position.

[0012] According to another aspect of the present invention, a patientsupport is provided that includes a frame, a mattress supported by theframe, and a siderail. The siderail includes a rail member having afirst longitudinal axis and a linkage assembly. The linkage assembly isconfigured to support the rail member on the frame and to have a secondlongitudinal axis. The linkage assembly is configured to permit rotationof the rail member about an axis of rotation. The axis of rotation andthe second longitudinal axis of the linkage assembly each have alongitudinal component relative to the first longitudinal axis.

[0013] Additional features of the present invention will become apparentto those skilled in the art upon consideration of the following detaileddescription of the preferred embodiment exemplifying the best mode ofcarrying out the invention as presently perceived.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014]FIG. 1 is side elevation view of a bed showing the bed including aframe having a deck with a head section thereof titled relative to theremainder of the frame and a head end siderail in a raised position;

[0015]FIG. 2 is a view similar to FIG. 1 showing the head end siderailin a lowered position;

[0016]FIG. 3 is a cross-sectional view of the head end siderail takenalong line 3-3 of FIG. 2;

[0017]FIG. 4 is side elevation view of a portion of the head endsiderail in the raised position showing the siderail including a pair ofspaced-apart links pivotably coupled to a longitudinally extended rod,the rod including two pairs of cylindrical cam members, and each linkincluding a pair of spaced-apart cylindrical cam members positioned tocontact the cylindrical cam members of the rod;

[0018]FIG. 5 is a view similar to FIG. 5 showing the siderail translatedto the right when in the lowered position;

[0019]FIG. 6 is a side view of a second embodiment siderail in a raisedblocking position;

[0020]FIG. 7 is a view similar to FIG. 8 of the siderail in a loweredegress position; and

[0021]FIG. 8 is a perspective view of the second embodiment siderailshowing the siderail including a linkage assembly coupled to the frameand a rail member, with portions broken away, coupled to the linkageassembly.

DETAILED DESCRIPTION OF THE DRAWINGS

[0022] As shown in FIG. 1, a hospital bed 10 is provided including aframe 11 positioned on the floor and including a sub-frame 12 and aupper frame or deck 14 supported by sub-frame 12, a mattress 13positioned on deck 14, a headboard 16 coupled to sub-frame 12, afootboard 18 coupled to deck 14, and a pair of split siderails 20, 21coupled to sub-frame 12. Sub-frame 12 is configured to raise and lowerdeck 14 relative to the floor and to move deck 14 to the Trendelenburgposition and the Reverse Trendelenburg position.

[0023] As shown in FIG. 1, sub-frame 12 includes a rectangular lowerframe member or base frame 32, a plurality of casters 50 coupled to baseframe 32 to permit hospital bed 10 to be rolled about a care facility, arectangular upper frame member or intermediate frame 52, a linkagesystem 54 coupled to intermediate and base frames 52, 32 to permitrelative motion therebetween, and an actuator system providing power toactuate linkage system 54 and move upper member 52 relative to baseframe 32. Linkage system 54 includes a pair of head links 58 pivotablycoupled to a head end 53 of intermediate frame 52 and slidably coupledto base frame 32, a pair of guide links 57 pivotably coupled torespective head links 58 and pivotably coupled to intermediate frame 52at a fixed pivot point, a pair of foot links 60 pivotably coupled to afoot end 55 of intermediate frame 52 and slidably coupled to base frame32, and a pair of guide links 62 pivotably coupled to respective footlinks 60 and pivotably coupled to intermediate frame 52 at a fixed pivotpoint.

[0024] Split siderails 20, 21 are pivotably coupled to respective headsection 24 of deck 14 and weigh frame 26. Each siderail 20, 21 isconfigured to move between raised blocking positions, as shown in FIG.1, and lowered egress positions, as shown in FIG. 2, to permit entry andegress of patients into and out of hospital bed 10. Each siderail 20, 21includes a respective rail member 34, 36 and a coupler or linkageassembly 38, 40 coupled between respective rail members 34, 36 andrespective head section 24 of deck 14 and weigh frame 26 that permitrail members 34, 36 to be moved between raised and lowered positions.

[0025] Linkage assembly 38 includes a first link 42 rigidly coupled torespective head section 24 of deck 14 and weigh frame 26, a pair ofcurved second links 44 pivotably coupled to first link 42, a third link46 pivotably coupled to second links 44, and a curved fourth link 48pivotably coupled to third and first links 42, 46. According toalternative embodiments of the present disclosure, other couplers areprovided such as “clocking” siderail linkage assemblies and othercouplers known to those of ordinary skill in the art for coupling a railmember to a bed frame.

[0026] First link 42 includes a base 64 coupled to intermediate weighframe 26 and four upwardly extending flanges 66 rigidly coupled to base64 as shown in FIG. 4. Each second link 44 includes a first end 68pivotably coupled to flanges 66 by a rod 70 and a looped second end 72pivotably coupled to third link 46 by a rod 74 as shown in FIG. 3.

[0027] Third link 46 includes a base 76, a first pair of inwardlyextending flanges 78 coupled to base 76, and a second pair of inwardlyextending flanges 80 also coupled to base 76 as shown in FIG. 2. Rod 74extends between flanges 78 and through second ends 72 of second link 44to provide the pivotable connection therebetween.

[0028] As shown in FIG. 2, fourth link 48 includes a base 82 and alatch-receiving slot 84 formed in base 82. A first end 86 of base isslidably and pivotably coupled to second pair of flanges 80 of thirdlink 46 by a rod 88. A second end 90 of base 82 is pivotably coupled tothe lower ends of flanges 66 of first link 42 by a rod 92. Thus, linkageassembly 38 provides a four bar linkage permitting siderails 20, 21 toswing sideways between the raised and lowered positions.

[0029] Each siderail 20, 21 further includes a retainer 94 configured to“bind” the four bar linkage to prevent siderails 20, 21 from moving fromthe raised position to the lowered position. As shown in FIG. 3,retainer 94 includes a Z-shaped latch member 96 positioned inlatch-receiving slot 84 and pivotably coupled to fourth link 48 by rod98 to move between a latched position, as shown in FIG. 3, and anunlatched position and a catch rod 100 coupled to first link 42 by apair of flanges 110. Rod 100 extends between flanges 110 as shown inFIG. 6. Latch member 96 includes a first end 112 that engages catch rod100 and a second end 114. A handle 116 is provided that is coupled tosecond end 114. First end 112 includes a notch 118 configured to receivecatch rod 100 therein to secure latch member 96 in the latched positionas shown in FIG. 3.

[0030] When first end 112 is latched onto catch rod 100, a three barlinkage is established between first link 42, latch member 96, andfourth link 48. This arrangement of linkages binds first link 42relative to fourth link 48 so that linkage assembly 38 is also boundfrom moving while latch member 96 is in the latched position to preventsiderails 20, 21 from swinging to the lower position.

[0031] To unbind linkage assembly 38 and permit siderails 20, 21 toswing to the down position, latch member 96 must be moved from thelatched position to the unlatched position. A caregiver can unlatchlatch member 96 by pulling downwardly and outwardly on handle 116 topivot latch member 96 in the clockwise direction. This movement pullsfirst end 112 of latch member 96 away from catch rod 100 so that latchmember 96 no longer binds first and fourth links 42, 48.

[0032] As shown in FIG. 4, assembly 38 further includes a gas spring ordashpot 120 coupled to first link 42 and third link 46. Gas spring 120is compressed when siderail 20, 21 is lowered to dampen the movement andprevent rapid lowering of rail member 34.

[0033] Because first and fourth links 42, 48 are free to pivot relativeto one another, linkage assembly 38 is also unbound and free to permitsiderails 20, 21 to swing between the raised and lowered positions. Aspring 122 is provided between a middle portion of fourth link 48 and aspring mount 124 coupled to a middle portion of latch member 96 to biaslatch member 96 toward the latched position. According to alternativeembodiments of the present disclosure, other retainers are provided tohold the siderails in the raised position such as clasps, catches,locks, other latches, clamps, pins, bolts, bars, hasp, hooks, or otherretainers known to those of ordinary skill in the art.

[0034] Head end siderails 21 are configured to move longitudinally, inthe directions of longitudinal axis 22, when raised and lowered. Whenlowered, head end siderail 21 moves in a first longitudinal direction126, shown in FIG. 4, by a distance 128 toward a head end of headsection 24 of deck 14. When raised, head end siderails 21 moves in asecond longitudinal direction 130, shown in FIG. 6, by distance 128 backtoward a foot end of head section 24.

[0035] The movement of siderails 20, 21 is also characterized bymovement in sideways directions 129, 131 as shown in FIG. 3. Thesideways movement in directions 129, 131 and the raising and loweringmovements of siderails 20, 21 in directions 133, 135 cooperate to definedirections 156, 158, respectively in which rail members 34, 36 travelduring raising and lowering. Therefore, the movement of siderails 20, 21between the raised and lowered positions have longitudinal components indirections 126, 130, as discussed above, along longitudinal axes 22 ofrail members 34, 36, up and down or vertical components, and sideways orhorizontal components in directions 129, 131.

[0036] According to an alternative embodiment of the present disclosure,clocking siderails are provided that have a cam assembly or sets of cammembers configured to move the respective rail member laterally orsideways relative to the mattress during raising and lowering of therail member. According to other alternative embodiments, cam members areprovided to move the rail member in other directions during raisingand/or lowering of the rail member.

[0037] By moving head end siderails 21 longitudinally when lowering,additional clearance is provided between head end siderail 21 and footend siderail 20. Thus, when head section 24 of deck 14 is in the raisedposition (as shown in FIG. 2), foot end siderail 20 is in the raisedposition (as shown in FIG. 2), and head end siderail 21 is lowered fromthe raised position, rail member 34 of head end siderail 21 is pushed indirection 128 so that contact with foot end siderail 20 is avoided.

[0038] As shown in FIGS. 5 and 6, linkage assembly 38 of head endsiderails 21 includes a first set of cam members 132 and a second set ofcam members 134. Each set of cam members 132, 134 includes a pair ofstationary cam members 136, 138 rigidly coupled to flanges 66 of firstlinks 42 and a pair of rotary cam members 140, 142 rigidly coupled tofirst ends 68 of second links 44. As shown in FIGS. 4 and 5, rod 70extends through rotary cam members 140, 142 to pivotably couple secondlinks 44 to first links 42. According to an alternative embodiment ofthe present disclosure, only one set of cam members are provided.

[0039] As shown in FIG. 5, each stationary cam member 136, 138 is atruncated cylinder that has a first substantially flat end surface 144coupled to flanges 66. Each respective stationary and rotary cam member136, 138, 140, 142 further includes an inclined cam surface 146, 148,150, 152 that cooperates with a longitudinal axis of rotation 154 of rod70 to define respective angles therebetween of approximately 45°.

[0040] As shown in FIG. 5, cam surfaces 146 of stationary cam members136 are substantially parallel with and slightly spaced-apart from camsurfaces 150 of rotary cam members 140 when head end siderail 21 is inthe fully raised position. Cam surfaces 148 of stationary cam members138 are spaced-apart from cam surfaces 152 of rotary cam members 142 anddefine an angle of approximately 90° therebetween.

[0041] When handle 116 is pulled, head end siderail 21 moves towards thelowered position. During this movement, rail member 34, second links 44,and rotary cam members 140 rotate in a clockwise direction 156, as shownin FIG. 5, so that cam surfaces 150 of rotary cam members 140 move intocontact with cam surfaces 146 of stationary cam members 136. As shown inFIG. 6, continued rotation of rotary cam members 140 create forcesbetween rotary cam members 140 and stationary cam members 136. Theseforces push rotary cam members 140, second links 44, and rail member 34of head end siderail 21 in direction 126. When head end siderail 21 ismoved to the lowered position, rail member 34 is pushed toward the headend of head section 24 by distance 128, as shown in FIG. 5.

[0042] As previously mentioned, third link 46 is slidably coupled tofourth link 48 by rod 88. During movement of rail member 34 of head endsiderail 21 in direction 126, fourth link 48 does not movelongitudinally so that third link 46 and rail member 34 slides relativeto fourth link 48.

[0043] When head end siderail 21 is initially moved toward the raisedposition, cam surfaces 148 of stationary cam members 138 are slightlyspaced-apart from cam surfaces 152 of rotary cam members 142. Camsurfaces 146 of stationary cam members 136 are slightly spaced-apartfrom cam surfaces 150 of rotary cam members 140.

[0044] As head end siderail 21 is moved further toward the raisedposition, rail member 34, second links 44, and rotary cam members 140rotate in a counterclockwise direction 158, as shown in FIG. 5, so thatcam surfaces 148 of stationary cam members 138 move into contact withcam surfaces 152 of rotary cam members 142. Continued rotation of rotarycam members 140 creates forces between rotary cam members 142 andstationary cam members 138. These forces push rotary cam members 142,second links 44, and rail member 34 of head end siderail 21 in direction130. During this movement, third link 46 and rail member 34 slidesrelative to fourth link 48 in direction 130.

[0045] As shown in FIG. 4, cam surfaces 146 of stationary cam members136 are substantially parallel with and slightly spaced-apart from camsurfaces 150 of rotary cam members 140 when head end siderail 21 is backto the fully raised position. Cam surfaces 148 of stationary cam members138 are spaced-apart from contact cam surfaces 152 of rotary cam members142 and define an angle of approximately 90° therebetween.

[0046] According to alternative embodiments of the present disclosure,other configurations of siderails that move in a longitudinal directionduring raising and lowering are provided. These alternative embodimentsincludes other configurations of cam members, links, belts, cable,pulleys, or other mechanisms known to those of ordinary skill in the artfor creating movement of a member in one direction based on movement ofthe same or another member in another direction.

[0047] For example, as shown in FIGS. 6-8, another embodiment of thedisclosure provides a hospital bed 310 including sub-frame 12 positionedon the floor, deck 14 coupled to sub-frame 12, a mattress 13 positionedon deck 14, headboard 16 coupled to sub-frame 12, footboard 18 coupledto deck 14, and a pair of split siderails 320, 321 coupled to frame 11.Sub-frame 12 is configured to raise and lower deck 14 relative to thefloor and to move deck 14 to the Trendelenburg position and the ReverseTrendelenburg position.

[0048] Split siderails 320, 321 include respective rail members 340, 341and couplers or linkage assemblies 342 coupled between respective railmembers 340, 341 and intermediate frame 52 that permit rail members 340,341 to be moved between raised and lowered positions as shown in FIGS. 7and 6. As shown in FIG. 8, linkage assemblies 342 each include a firstlink 344 rigidly coupled to intermediate frame 52, a pair of curvedsecond links 346 pivotably coupled to first link 344, a third link 348pivotably coupled to second links 346, and a curved fourth link 350pivotably coupled to third and first links 344, 348. Each of second 346and fourth 350 links has a longitudinal axis 347, 351 that cooperate todefine a general longitudinal axis 343 of linkage assembly 342. Railmembers 340, 341 are coupled to third link 348.

[0049] Linkage assemblies 342 are fixed to intermediate frame 52 suchthat the longitudinal axes of second 346 and fourth 350 links are notperpendicular to a plane defined by intermediate frame 52 that isparallel to a plane defined by the patient support surface of mattress13. In the raised position, longitudinal axis 343 of linkage assembly342 has a vertical component parallel to vertical axis 396 and alongitudinal and horizontal component parallel to longitudinal axis 398of rail member 340. Therefore, longitudinal axis 343 of linkage assembly342 is not parallel with or perpendicular to longitudinal axis 398 ofrail member 340.

[0050] First link 344 includes a base 352 coupled to intermediate frame52 by fasteners 140 and four angled upwardly extending flanges 354rigidly coupled to base 352. Each second link 346 includes a loopedfirst end 356 pivotably coupled to flanges 354 by a rod 358 and a loopedsecond end 360 pivotably coupled to third link 348 by a rod 362 as shownin FIG. 8. Rods 358, 362 are perpendicular to angled flanges 354 and notparallel to the plane of the intermediate frame 52. Further, secondlinks 346 are perpendicular to rods 358, 362 such that first link 344 isnot aligned directly above or below third link 348 when rail 320, 321 isin the raised or lowered position. Rather, third link 348 islongitudinally displaced toward or away from headboard 16 or footboard18 relative to first link 344.

[0051] Third link 348 includes a base plate 364, a first pair of angledinwardly extending flanges 366 coupled to base plate 364, and a secondpair of angled inwardly extending flanges 368 also coupled to base plate364 as shown in FIG. 8. Rod 362 extends between flanges 366 and throughsecond ends 360 of second link 346 to provide the pivotable connectiontherebetween.

[0052] As shown in FIG. 8, fourth link 350 includes a base 370 and alatch-receiving slot 372 formed in base 370. A first end 374 of the base370 is pivotably coupled to second pair of flanges 368 of third link 348by a rod 376. Similarly, a second end 377 of base 370 is pivotablycoupled to the lower ends of flanges 354 of first link 344 by a rod 378.Thus, linkage assembly 342 provides a four bar linkage permittingsiderails 320, 321 to swing sideways between raised and loweredpositions.

[0053] As previously stated, linkage assemblies 342 are fixed to theintermediate frame 52 such that longitudinal axes 343 of linkageassemblies 342 are not perpendicular to a plane defined by intermediateframe 52. Therefore, as siderails 320, 321 swing between raised andlowered positions, siderails 320, 321 travel longitudinally indirections 324, 326. Second links 346 and fourth links 350 rotate aboutrods 358, 378. As shown in FIG. 8, rods 358 and 378 each have an axis ofrotation 359, 379 that cooperate to define an overall axis of rotation345 for linkage 342. The overall axis of rotation 345 has a verticalcomponent in direction 393 parallel with vertical axis 396 and alongitudinal horizontal component in direction 324 parallel withlongitudinal axis 398 of rail member 340. Therefore, axis of rotation345 is not parallel with or perpendicular to longitudinal axis 398 ofrail member 340 at any time when rail member 340 is stationary or duringmovement between the raised and lowered positions. Further, whenmattress 13 is in a flat bed position, as shown in FIGS. 6 and 7, axisof rotation 345 is not horizontal.

[0054] Each siderail 320, 321 further includes a retainer 380 configuredto bind the four bar linkage to prevent siderails 320, 321 from movingfrom the raised position to the lowered position. As shown in FIG. 8,retainer 380 includes a Z-shaped latch member 382 positioned inlatch-receiving slot 372 and pivotably coupled to fourth link 350 by rod384 to move between a latched position, as shown in FIG. 8 and anunlatched position. The retainer 380 also includes a catch rod 386coupled to first link 344. Rod 386 extends between angled flanges 354 offirst links 344. Rod 386 is parallel to rods 358, 378, 384 and notparallel with the plane of intermediate frame 52. Latch member 382includes a first end 388 that engages catch rod 386 and a second end390. A patient-inaccessible release or handle 392 is provided that iscoupled to second end 390. First end 388 includes a notch 394 configuredto receive catch rod 386 therein to secure latch member 382 in thelatched position as shown in FIG. 8.

[0055] When first end 388 is latched onto catch rod 386, a three barlinkage is established between first link 344, latch member 382, andfourth link 350. This arrangement of linkages binds first link 344relative to fourth link 350 so that linkage assembly 342 is also boundfrom moving while latch member 382 is in the latched position to preventsiderails 320, 321 from swinging to the lowered position.

[0056] As previously discussed, when siderails 320, 321 swing into thelowered position, the downward movement is accompanied by longitudinalmovement as shown in FIGS. 6 and 7. The longitudinal movement associatedwith downward movement for head end siderail 321 is typically towardsheadboard 16 in direction 324 without any return movement in direction326. Preferably, downward movement for head end siderail 321 isassociated with longitudinal movement towards the headboard 16 indirection 324. The longitudinal movement associated with the downwardmovement of foot end siderail 320 is typically toward footboard 18 indirection 326. Preferably, similar to head end siderail 321, alldownward movement the foot end siderail 320 is associated withlongitudinal movement towards the footboard 18 in direction 326 withoutany return movement in direction 324. All upward movement of siderails320, 321 is then associated with longitudinal movement in direction 324,opposite the longitudinal movement experienced during downward movement.Alternatively, upward and downward movement of siderails 320, 321 ischaracterized by longitudinal movement primarily in one direction 324,326 but with some return movement in the opposite direction 326, 324.When both siderails 320, 321 are lowered, each is displaced away from amidpoint 400 between head board 16 and foot board 18. This displacementcreates a space between the lowered siderails 320, 321 allowing accessto the area beneath the mattress 13. This displacement also allowsaccess to any foot controls or other devices that may be located on theframe like those disclosed in U.S. patent application Ser. No.09/750,741, entitled Hospital Bed, to Osborne et al., the disclosure ofwhich is expressly incorporated by reference herein.

[0057] According to other embodiments, it is not necessary that linkageassembly 342 be utilized on both head end and foot end siderails 321,320. One of siderails 320, 321 employs linkage assembly 342 thatlongitudinally displaces rail member 340 and other siderail 320, 321employs a linkage assembly that does not longitudinally displace railmember 141, 143.

[0058] According to other embodiments, linkage assembly 342 isconfigured to rotate 180° as it moves from the raised position to thelowered position. Longitudinal axis 343 defined by linkage assembly 342in the raised position is collinear with longitudinal axis 343 definedby linkage assembly 342 in the lowered position.

[0059] In another embodiment, linkage assembly 342 is employed in bed310 where siderails 320, 321 are attached to deck 14. By so attaching,siderails 320 321 articulate with the section 22, 24, 26, or 28 of deck14 to which siderails 320, 321 are attached as respective section (22,24, 26, 28) are tilted relative to intermediate frame 52. In embodimentsthat do not employ linkage assembly 342, head end rails 321 maysometimes hit foot end rails 320 when head end rails 321 are loweredfrom the raised position to the lowered position. By employing linkageassembly 342, head end rail 321 will move towards head board 16 as it islowered, thereby allowing head end rail 321 to lower without contactingfoot end rail 320.

[0060] According to alternative embodiments of the present disclosure,other configurations of couplers are provided to provide longitudinal orother movement during raising or lowering of the rail member. Forexample, according to one embodiment of the present disclosure, clockinglinkages are provided that have an axes of rotation that have alongitudinal component in addition to a lateral component. Thus, whenthe rail member is clocked from the raised position to the loweredposition, the rail member moves laterally away from or toward themattress.

[0061] Although the invention has been described in detail withreference to preferred embodiments, variations and modifications existwithin the scope and spirit of the invention as described and defined inthe following claims.

1. A patient support comprising a frame, a mattress supported by theframe, and a siderail supported by the frame, the siderail includes arail member and a linkage assembly configured to permit movement of therail member between a raised position blocking egress of a patientpositioned on the mattress and a lowered position, the linkage assemblyincluding a first stationary cam member, a first rotary cam memberpositioned to contact the first stationary cam member to move the railmember along a longitudinal axis in a first direction when the railmember is moved to the lowered position, a second stationary cam member,and a second rotary cam member positioned to contact the secondstationary cam member to move the rail member along the longitudinalaxis in a second direction opposite the first direction when the railmember is moved to the raised position.
 2. A patient support comprisinga frame, a mattress supported by the frame, and a siderail supported bythe frame, the siderail includes a rail member and a coupler configuredto couple the rail member to the frame and permit movement of the railmember between a raised position blocking egress of a patient positionedon the mattress and a lowered position, the coupler including a camassembly configured to move the rail member in a first direction duringmovement of the rail member.
 3. The patient support of claim 2, whereinthe cam assembly includes a first cam set having first and second cammembers configured to contact one another to move the rail member in thefirst direction.
 4. The patient support of claim 3, wherein the firstcam member is configured to rotate about an axis of rotation relative tothe second cam member.
 5. The patient support of claim 4, wherein theaxis of rotation is parallel to a longitudinal axis of the rail member.6. The patient support of claim 4, wherein each of the first and secondcam members have a cam surface and at least one of the cam surfacescooperates with the axis of rotation to define an angle of forty-fivedegrees.
 7. The patient support of claim 4, wherein at least one of thefirst and second cam members is configured to slide along the axis ofrotation during rotation of the first cam member.
 8. The patent supportof claim 3, wherein the coupler further includes a link coupled to therail member and the first cam member.
 9. The patient support of claim 7,wherein the link is pivotably coupled to the rail member.
 10. Thepatient support of claim 7, wherein the first cam member is configuredto rotate about an axis of rotation relative to the second cam member.11. The patient support of claim 10, wherein the first cam member isconfigured to move along the axis of rotation during rotation of thefirst cam member relative to the second cam member.
 12. The patientsupport of claim 3, wherein the cam assembly further includes anothercam set having third and fourth cam members configured to contact oneanother to move the rail member.
 13. The patient support of claim 12,wherein the coupler further includes a first link coupled to the firstcam member and the rail member and a second link coupled to the thirdcam member and the second link.
 14. The patient support of claim 12,wherein the first and second links are pivotably coupled to the railmember.
 15. The patient support of claim 3, wherein the first and secondcam members have complementary angled cam surfaces.
 16. The patientsupport of claim 3, wherein the first and second cam member havecongruently angled cam surfaces.
 17. The patient support of claim 3,wherein one of the cam member is configured to rotate about an axis ofrotation relative to the other cam member.
 18. The patient support ofclaim 3, wherein the first cam member is configured to slide relative tothe second cam member.
 19. The patient support of claim 3, wherein thefirst cam set further includes a third cam member configured to contactthe first cam member to move the rail member in a second directionopposite the first direction.
 20. The patient support of claim 2,wherein the rail member has a longitudinal axis and the cam assembly isconfigured to move the rail member in a first longitudinal direction.21. The patient support of claim 20, wherein the cam assembly isconfigured to move the rail member in the first direction duringlowering of the rail member.
 22. The patient support of claim 21,wherein the cam assembly is configured to move the rail member in asecond direction opposite the first direction during raising of the railmember.
 23. The patient support of claim 20, wherein the cam assembly isconfigured to move the rail member in the first direction during raisingof the rail member.